A Peoria mother and her teenage son pleaded not guilty this morning to murder charges, about six weeks after police said the two hired a 16-year-old boy to kill a member of their family.

Police said at the time that Michelle Gibson called 911 early on March 1 saying she found her husband dead in the garage. According to police, while investigators were at the house, 16-year-old Erik McBee walked up to the murder scene with a 14-year-old girl and told police he did it.

McBee was charged with first-degree murder and the 14-year-old was questioned and released. A few weeks later, police released the details of a bizarre murder plot.

Police discovered that Steve Gibson's wife, Michelle, and their son, Steven Gibson Jr., told McBee and another 16-year-old boy that Steve Gibson was a danger to them and that they should help protect their friend -- by killing him, for which they would collect $1,000.

The other 16-year-old boy backed out that night because his parents called him and told him to come home, but McBee stayed.

According to police, Michelle Gibson and her son went out, while McBee went to Steve Gibson's bedroom and hit him multiple times with a baseball bat. He left the scene, then came back to find Gibson still alive, so he hit him several more times with the bat and cut his throat with a knife, police say.

Steve Jr. was then dropped off at the house by his mother, and he allegedly stabbed his father a few times, too, police say.

Gibson's body was then placed in the garage, as they planned to transport his body to a park, where it apparently would look as though he got killed for drugs, police say.

McBee got spooked, though, and ran off, so the Gibsons ended up staging the body in the garage, before Michelle Gibson called police saying she'd just found her husband's body.

The Gibsons and McBee all have pleaded not guilty to charges, and police said two weeks ago that there were three other people who were either involved or knew about the plot, but they haven't been arrested.